I'm probably going to do it if they ever get around to doing the 66 gauge.
The 66-73 AMP gauge actually works, but you have to clean the connections between the gauge and alternator to do it. Many times I have seen them go from "dead" to full travel just by doing that. Lotta work, though.
Amateur restorer. (Well, once in a while I have been paid for it)
One wire to any ground point in the car.
One wire to any good source of +12volts in the car.
Preferablly really close to the + terminal of the battery.
The further away from the battery or on a circuit that pulls lots of current will create errors in the voltage reading due to voltage drops.
The most accurate way is a dedicated wire from the voltmeter to the +terminal on the battery.
Everybody has to start some place
The supplier is Rocketman Innovations. Wiring consists of connecting the + to Switched ignition circuit and ground for the neg. The new gauge will read centered at 12.5 volts and will read to the far left when off. Warranty for life, gauge face is restored and new movement is brand new air core style.
April 23, 2013: After much work and frustration, I have decided to drop the 65-66 voltmeter project. The main component I was hoping to use is still not available with no release date in sight and I have not come up with another sellable P&P solution. The guys over on the Vintage Mustang Forum have used a SunPro aftermarket gauge in their dash; the thread about it is here: ammeter to voltmeter conversion
1966 Mustang Convertible - Pony Car
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